White-leaved Lawyer

Rubus schmidelioides is a dicot liana and is a dense shrub with intertwining branchlets. It is a perennial plant that grows up to 10 metres (33 ft) long, or forms a bush when there is no support nearby. It ascends its host using small reddish hooks along its stems. The stems are long and tapering, up to 10 centimetres (4 in) in diameter. It has branchlets up to 40 mm (1.6 in) in diameter. These are covered in short soft hair when young but become hairless and smooth when mature, and grow large red spikes. It has small narrow stipules and petioles which are around 20 mm (0.79 in) long. The leaves are glossy, ranging from orange to green/brown, and are arranged in a compound palmate pattern with 3–5 leaflets. The leaflets are terminal with an oval, oblong or lanceolate shape. There is a clear midrib on the leaves and they have a serrated margin. The bottom sides are grey-white. The leaflets are glabrous on the upper surface but hairy along the underside, with hair colour ranging from white, brown or grey. The leaves often curl downwards. Leaflets are commonly 2–6 cm (0.79–2.36 in) long, 2.5–3.5 cm (0.98–1.38 in) wide and the petiolule is on average 10–50 mm (0.39–1.97 in) long. In juvenile plants, leaflets are narrower and more glabrous compared to the mature forms. In open scrubland environments, however, mature plants retain their juvenile leaves. This variant is called var. …

Rubus schmidelioides var. schmidelioides and its variant var subpauperartus are both endemic to New Zealand and the Chatham islands. It is found mainly in the South Island in eastern Canterbury but can also be found in other areas of the country and on Stewart Island.

Rubus schmidelioides is found primarily in scrub and forest. Its variant, Rubus schmidelioides var. subpauperatus, can be found in open scrublands or exposed rocky sites. It has previously been found in the driest vegetation zones surrounding lakes and in a freshwater wetland near the Waitangiroto River. Rubus schmidelioides grows best during the mid-stages of succession when the tree canopies have not grown high. Juveniles struggle to grow in areas of low light where the canopy is already established. Rubus schmidelioides favors environments with alluvial soils and appears to be more common in indigenous forests.

A gall mite Acalitus rubensis commonly feeds on R. schmidelioides and causes erineum on the underside of the leaflets in the process. The adults of the endemic beetle Eucolaspis feed on the leaves. Endemic caterpillars of the moth Heterocorssa rubophaga feed in flowers, on fruit and the young shoots of R. schmidelioides, and induce gall on the stems. An endemic flat mite species Tenuipalpus rangiorae feed on R. schmidelioides leaves and lay eggs on the surface of the leaflets. The larvae of gall flies, one leaf vein, one stem and petiole gall species and one stem gall species inflict galls on the upper side of the leaflets, mid ribs of the leaf and stems respectively. An endemic species of scale insect feeds on R. schmidelioides and causes sooty mold on its leaflets. Rubus schmidelioides leaflets and fruit are both eaten by possums and leaflets are also browsed by introduced deer, although neither have a large impact on R. schmidelioides distribution. Rubus schmidelioides is susceptible to both European blackberry rust and the rust species Kuehneola uredines. Kererū, kākā, riflemen, pipipi, grey warbler, fantail and silvereye are all observed to eat R. schmidelioides berries. The woody twigs and leaflets were likely grazed by moa before their extinction. The plant has domatia. Rubus schmidelioides is pollinated by the introduced honey bee and the endemic bee Lasioglossum.

Noticing similarities to European wild blackberries, Early European settlers in New Zealand used tātarāmoa berries to create foods such as preserves or jams.

The Māori language name tātarāmoa is used in other Polynesian languages to refer to plants of the genus Caesalpinia, which while unrelated, have spiky fruits. The name refers to spurs on rooster feet. Other name used in Māori is akatātarāmoa. The English language name lawyer is used for a number of scrambling varieties of Rubus, and likely refers to the hooks of the plant being difficult to remove.